When to stop - a cardinal secretary search experiment

The cardinal secretary search problem confronts the decision-maker with more or less candidates who have identically and independently distributed values and appear successively in a random order without recall of earlier candidates. Its benchmark solution implies monotonically decreasing sequences of optimal value aspirations (acceptance thresholds) for any number of remaining candidates. We compare experimentally observed aspirations with optimal ones for different numbers of (remaining) candidates and methods of experimental choice elicitation: “hot” collects play data, “warm” asks for an acceptance threshold before confronting the next candidate, and “cold” for a complete profile of trial-specific acceptance thresholds. The initially available number of candidates varies across elicitation methods to obtain more balanced data. We find that actual search differs from benchmark behavior, in average search length and success, but also in some puzzling qualitative aspects

Partial versus general compulsory solidarity: an experimental analysis

We focus on ways and means of solidarity and their more or less voluntary and involuntary character. Alternative ways of redistribution are modeled by combining redistribution as emergent from a non-discriminatory voluntary contribution mechanism, VCM, with an outside option for a “super-rich”, R, participant to donate to VCM participants. The outsider may discriminate between participants of the VCM on the basis of information accessible at a cost to her. Inclusion in and exclusion from the VCM are involuntary while contributions in it are voluntary. How involuntary inclusion of R in VCM affects her discriminatory voluntary donations and contribution behavior is explored experimentally

Rank-order competition in the voluntary provision of impure public goods

Publicly provided goods often create differential payoffs due to timely or spatial distances of group members. We design and test a provision mechanism which utilizes rank competition to mitigate free-riding in impure public goods. In our Rank-Order Voluntary Contribution Mechanism (Rank-Order-VCM) group members compete via observable contributions for a larger share of the public good; high contributors receive preferential access (a larger share), while low contributors receive restricted access (a lower share). In a laboratory experiment Rank-Order-VCM elicits median contributions equal to the full endowment throughout the finitely played games with constant groups. In the control treatment, with randomly assigned ranks, the contributions are significantly lower and decline over time. We thus provide evidence of rank competition, in situations where discriminatory access to public goods is possible, being efficiency enhancing

Equal and unequal profit sharing in highly interdependent work groups: a laboratory experiment

We study behavior in a simplified representation of an organization with high task interdependence. The production process involves three stages such that output of earlier stages is the necessary input for subsequent stages. Work at earlier stages is easier than at later stages and the product is only final if it goes successfully through the highest stage. We compare the effects on the performance of the organization of a payment scheme in which profits are equally shared by all those involved in the production process with one where the participation in profits is strongly increasing in the production stage. The comparison is made for two ways of assigning individuals to the production stage: randomly or by merit. We find that initially there is no difference in the organization’s profit between the two sharing schemes, but over time profits increase more with the equal sharing scheme. Changes in profits over time can be explained by changes in production performance over time. After participants have gained experience in the tasks, the equal profit sharing scheme has positive performance effects both at the lowest and the highest production stages. There are only minor differences in the results depending on whether the payment scheme is exogenously imposed or chosen by the person at the highest stage

Trusting versus monitoring: an experiment of endogenous institutional choices

We investigate the problem of deciding between trusting and monitoring, and how this decision affects subsequent behavior, using a laboratory experiment where subjects choose between the Ultimatum and the Yes-No Game. Despite the similarity of the two games in Ultimatum Games responders monitor the allocation proposal, while in Yes-No games responders react without monitoring, i.e. have to rely on trust. We permit either the proposer or responder to make the game choice and analyze how both roles choose between trusting and monitoring, what the ensuing effects of their choices are, and how they vary depending on who has chosen the game. We, also, experimentally vary the cost of monitoring and the responder’s conflict payoff. Since monitoring is usually costly, the amount to share in Yes-No Games (YNG) can exceed that in Ultimatum Games (UG). Regarding the conflict payoff, it can be positive or negative with the former rendering Yes-No interaction a social dilemma. According to our results, proposers (responders) opt for trusting significantly more (less) often than for monitoring. Average offers are higher in Ultimatum than in Yes-No games, but neither UG nor YNG offers depend on who has chosen between games

Telling the other what one knows? Strategic lying in a modified acquiring-a-company experiment with two-sided private information

Lying for a strategic advantage is to be expected in commercial interactions. But would this be more or less obvious when lying could come from either party and question mutually profitable exchange? To explore this, we modify the acquiring-a-company game (Samuelson and Bazerman in Res Exp Econ 3:105–138, 1985) by letting both, buyer and seller, be privately informed. Specifically, the value of the company for the buyer is known only by the seller; whereas, only the buyer is aware by which proportion the sellers evaluation is lower than that of the buyer. Before bargaining, both parties can reveal what they know via cheap-talk numerical messages. Game theoretically, the pooling equilibrium may or may not allow for trade depending on the commonly known expected evaluation discrepancy. By mutually revealing what one knows, one could boost trade and efficiency. Although strategic misreporting prevails quite generally, it is higher for sellers throughout the experiment. Regarding gender, women misreport less, especially as sellers, and offer higher prices

Behavioral spillovers in local public good provision: an experimental study

In a circular neighborhood, each member has a left and a right neighbor with whom(s) he interacts repeatedly. From their two separate endowment amounts individuals can contribute to each of their two structurally independent public goods, either shared only with their left, respectively right, neighbor. If most group members are discrimination averse and conditionally cooperating with their neighbors, this implies intra- as well as inter personal spillovers which link all neighbors. Investigating individual adaptations in one’s two games with differing freeriding incentives confirms, through behavioral spillovers, that both individual contributions anchor on the local public good with the smaller free-riding incentive. Therefore asymmetry in gaining from local public goods allows to establish a higher level of voluntary cooperation

Does heterogeneity spoil the basket? The role of productivity and feedback information on public good provision

In a circular neighborhood of eight, each member contributes repeatedly to two local public goods, one with the left and one with the right neighbor. All eight two-person games provide only local feedback information and are structurally independent in spite of their overlapping player sets. Heterogeneity is induced intra-personally by asymmetric productivity in left and right games and inter-personally by two randomly selected group members who are less privileged (LP) by being either less productive or excluded from end-of-period feedback information about their payoffs and neighbors’ contributions. Although both LP-types let the neighborhood as a whole evolve less cooperatively, their spillover dynamics differ. While less productive LPs initiate “spoiling the basket” via their low contributions, LPs with no-end-of-round information are exploited by their neighbors. Furthermore, LP-positioning, closest versus most distant, affects how the neighborhood evolves

MRI sensing based on the displacement of paramagnetic ions from chelated complexes

We introduce a mechanism for ion sensing by MRI in which analytes compete with paramagnetic ions for binding to polydentate chelating agents. Displacement of the paramagnetic ions results in alteration of solvent interaction parameters and consequent changes in relaxivity and MRI contrast. The MRI changes can be tuned by the choice of chelator. As an example, we show that calcium-dependent displacement of Mn[superscript 2+] ions bound to EGTA and BAPTA results in a T[subscript 1]-weighted MRI signal increase, whereas displacement from calmodulin results in a signal decrease. The changes are ion selective and can be explained using relaxivity theory. The ratio of T[subscript 2] to T[subscript 1] relaxivity is also calcium-dependent, indicating the feasibility of “ratiometric” analyte detection, independent of the probe concentration. Measurement of paramagnetic ion displacement effects could be used to determine analyte ion concentrations with spatial resolution in opaque specimens.National Institutes of Health (U.S.) (grant DP2-OD2441)National Institutes of Health (U.S.) (grant R01-GM65519)McGovern Institute for Brain Research at MIT. Neurotechnology (MINT) Progra